Continuity mistake: During the first set of cruise scenes, you can see a shot of a yellow '56 Chevy parked on the opposite side of the street with the hood raised and a coupe of guys working on the engine (just after a purple-ish '40 Ford rolls past). In the very next shot, you can see the same car for a very brief moment, this time with the hood down. A few shots later, you see the same yellow '56 yet again, but this time being driven. Finally, in the very next shot, Milner drives past it yet again, still parked on the side of the street, with the hood down. (00:10:14)
Continuity mistake: The girls - whose car tires are about to be flattened and windows about to be sprayed with shaving cream - roll up their passenger window twice during the same brief scene. Once as Milner and Carol are getting out of his hot-rod, and again as John and Carol approach the car. (00:59:00)
Continuity mistake: When Curt is saying his goodbyes prior to boarding, there is a person getting ready to climb the airplane stairs. When the camera changes angle, the person disappears. (01:47:34)
Continuity mistake: When Falfa's Chevy flips over, we can see that it has no fuel tank at all in it. However, in the next shot the car now has a visible fuel tank, and it explodes.
Continuity mistake: In close ups of Milner driving, watch the rolled up package of cigarettes in his T-shirt sleeve. In different shots you can see the front of the pack and the back of the pack, when there has not been time for him to have another.
Continuity mistake: When Toad turns the 58 Impala around to pick up Debbie. She walks past the same Blue Corvair twice. She then steps from the curb to talk to Toad. The Corvair is parked next to the curb. When they switch to the long shot the Corvair has been replaced by a gold coloured Buick. When they drive away the Corvair reappears in its original position.
Continuity mistake: After Carole is hit with the water balloon thrown from a passing car, she tells John Milner to catch them at the light, where he's to flatten their tyres while she sprays the windshield with shaving cream. Carole sprays the front windshield, then starts to go to the back of the car to spray the back window. The front windshield is clean, even though Carole just emptied a can of shaving cream onto it.
Continuity mistake: Just as John was about to stop his car to let Carol in for the first time, he passed a dark color 4-door sedan parked at the curb. Then Carol runs around to get into John's car, the dark sedan disappeared and there is a blue 1955 Plymouth in its place.
Continuity mistake: Terry wears blue jeans throughout the whole film. Except when Debbie starts talking to him about how she likes tuck and roll interior, he gets out of his car and all of a sudden he's wearing khakis.
Continuity mistake: When the '55 Chevy crashes, it comes to rest upside down with the trunk lid open. Moments later when it bursts into flames, the trunk lid is closed.
Continuity mistake: After the opening credits, when the guy drives up on the scooter, he crashes into a garbage bin. In the short time it takes Richard Dreyfuss to walk over and join them, the bin is back together and the scooter has changed position.
Continuity mistake: After Falfa crashes his chevy, he walks away from the crash with his hat in his hand. In the next scene John is holding the hat and hands it back to him.
Continuity mistake: When John is driving in his Ford and talking to the girl in the Studebaker, he drives past the same store "Marin Cameras" twice.
Continuity mistake: A windshield wiper is visible on Milner's coupe in only three shots. These occur when Carole gets into the coupe from the Studebaker and shortly after, when Milner is pulled over for a defective license plate light. All other shots of the coupe show only the stub of the wiper mechanism.
Continuity mistake: When Wolfman Jack was eating a popsicle, it had a cellophane wrapper, in those days they only had paper wrappers.
Continuity mistake: In the studio scene at XERB, Wolfman Jack takes the pickup arm off a spinning record. Then in the next scene, the arm is back on, and once again he takes it off, for it to be there on the disc a third time the next time it is in shot.
Continuity mistake: The movie takes place in 1962, yet the band at the dance is playing The Kingsmen version of Louie Louie which didn't come out until 1963.
Continuity mistake: Curt waits in his Citroen for a phone call from the Blonde in the T-Bird. He is sleeping and the camera shot shows him about 15 feet away from the phone booth. The phone ringing awakens him. The following shot shows him coming to and dashing for the phone. After exiting the car, he takes about two steps, and he's already in the phone booth. Either the car had magically been moved up closer to the phone booth for that shot, or he averages about 7 to 8 feet per step to reach the phone in time.
Continuity mistake: In one scene John Milner's coupe has a wiper blade. In the next scene, it is gone. It comes and goes.
